Ayper BOĞA, Yaşar SERTDEMİR, Seçil BİNOKAY

The toxicity and teratogenicity of gibberrellic acid ($GA_3$) based on the frog embryo teratogenesis assay-Xenopus (FETAX)

Çalışmada, bitki büyüme düzenleyicisi gibberellik asitin ($GA_3$)(bir pestisit tipi) potansiyel gelişimsel toksisitesi FETAX testi kullanılarak değerlendirildi. Xenopus laevis embriyoları (evre 8-11); 96 saatlik statik yenileme test koşullarında, gibberellik asitin 11 konsantrasyonuna maruz bırakıldı. Muamelenin sonucunda, ortalama letal konsantrasyon ($LC_{50}$), ortalama malformasyon (EC50), etkinin hiç görülmediği konsantrasyon (NOAEC) ve etkinin ilk görüldüğü en düşük konsantrasyon (LOAEC) saptandı. Gibberellik asite muamele sonucu Xenopus embriyolarında elde edilen LC50 ve EC50 değerleri sırayla 1117,5 mg/L and 658 mg/L, TI ($LC_{50}/EC_{50}$) değeri ($GA_3$)= 1,69 olarak bulundu. Gibberellik asit konsantrasyonunun artışına paralel olarak embriyolarda farklı tip anomaliler gözlendi. Bu sonuçlara göre, gibberellik asitin Xenopus laevis embriyoları için toksik ve teratojenik bir madde olduğunu söyleyebiliriz. Ayrıca, elde ettiğimiz sonuçlar FETAX’ın tarımda kullanılan kimyasalların biyolojik zarar değerlendirmesinde bir ön test olarak kullanılabileceğini teyit etmektedir.

Gibberellik asit'in ($GA_3$) toksisite ve teratojenitesinin kurbağa embriyo teratogenezis testi (FETAX) kullanılarak değerlendirilmesi

This study investigated the developmental toxicity of a plant growth regulator (a type of pesticide) using the frog embryo teratogenesis assay-Xenopus (FETAX). Xenopus laevis embryos were exposed to 11 different concentrations of gibberellic acid ($GA_3$), from stage 8 to 11, for 96 h under static renewal test conditions. The median lethal concentration ($LC_{50}$), malformation ($EC_{50}$), non-observed adverse effect concentration (NOAEC), and lowest observed adverse effect concentration (LOAEC) were calculated. The corresponding ($LC_{50}$) and ($EC_{50}$)values determined for GA3exposure were 1117.5 mg/L and 658 mg/L, respectively. The TI (LC50/EC50) value calculated for ($GA_3$) was 1.69. Different anomalies occurred in the embryos, depending on the ($GA_3$) concentration. Based on these results, we conclude that ($GA_3$) is toxic and teratogenic to Xenopus laevis embryos. Moreover, our results confirm that the FETAX assay can be a useful pretest for integrated biological hazard assessment of chemical agents used in agriculture.

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